How to restore menus after unregistering a menu-altering-add-on?
You add this to the unregister function, pointing the the UI script of the affected editor:
    bpy.ops.script.python_file_run(filepath= bpy.utils.resource_path(type=&quot;LOCAL&quot;)+&quot;\\scripts\\startup\\bl_ui\\space_sequencer.py&quot;)
    bpy.ops.script.reload()